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Targeting Cerebral Muscarinic Acetylcholine Receptors with Radioligands for Diagnostic Nuclear Medicine Studies

  • Daniel W. McPherson
Part of the Methods in Pharmacology and Toxicology book series (MIPT)

Abstract

Nerve cells communicate via the release of chemical messengers (neurotransmitters) which bind to a site (receptor) on another or the same cell causing an effect. The various neuroreceptor classes are responsible for important functions such as movement, memory, and learning. Naturally occurring neurotransmitters are agonists, molecules that trigger an effect in the target cell after binding to the receptor site. In most cases, the binding period of an agonist to the receptor is short and after release from the receptor, the agonist is rapidly taken up by the same nerve cell (reuptake) or metabolized by various bioenzymes. Antagonists are artificial “false” neurotransmitters that bind to a receptor, often with similar or higher affinity compared to an agonist, but do not cause an effect in the target receptor other than preventing the binding of the agonist. Typically, antagonists are designed to increase the binding affinity to the receptor site, to delay release from the receptor pocket, and inhibit the metabolism by bioenzymes.

Keywords

Positron Emission Tomography Single Photon Emission Compute Tomography Single Photon Emission Compute Tomography Study Cerebral Region Positron Emission Tomography Imaging Study 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Humana Press Inc. Totowa, NJ 2001

Authors and Affiliations

  • Daniel W. McPherson
    • 1
  1. 1.Nuclear Medicine Group, Life Sciences DivisionOak Ridge National LaboratoryOak Ridge

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